public class VlaueDemo {
    public static void main (String[] args) {

        int renshu = 0;

        renshu = renshu + 1;

        renshu = renshu + 2;
        renshu = renshu - 1;

        renshu = renshu + 2;
        renshu = renshu - 1;

        renshu = renshu - 2;
        renshu = renshu + 1;

        System.out.println("车上总计多少人" + renshu);
    }
}